Auswahl der wissenschaftlichen Literatur zum Thema „CHINA TREE YELLOW“

Abstract This article attempts to cast doubt on prior scholarship regarding Maoist environmental rhetoric regarding forestry, which has tended to characterize it as destructive, militaristic, and irrationally extractive. Against this simplistic portrayal of Maoist rhetoric concerning Chinese forestry and Mao Zedong’s attitudes toward nature, this article demonstrates that the rhetoric of forestry and environment in general during Mao’s period is scientific, rational, and even constructive regarding tree planting. To demonstrate the rational and premeditated aspect of socialist forestry and environmental history, the article first explores the speeches and writings of Japan and Germany educated Liang Xi, probably the most important forester in early socialist China, who advocated tree planting as a way of tackling the problem of the scarcity of trees. During the early 1950s, his firm belief that tree planting could solve the problems of the Yellow River clashed with hydrologists who also aspired to solve China’s environmental challenges. Using newspaper reports from the People’s Daily, the article then examines the rhetoric of the “Greening the Motherland” campaign launched by Mao in 1956. During this campaign, Mao pushed the Yellow River’s tree-planting initiative to a national scale, thanks largely to the foresters’ concerted efforts of persuasion. This nationwide campaign, in concert with the new regime's state-building efforts, required foresters to instill knowledge of tree planting in a broad range of people at the grassroots level as well as to strategically integrate it within the socialist revolutionary and global environmental discourse.

Tree aging is a new research area and has attracted research interest in recent years. Trees show extraordinary longevity; Platycladus orientalis L. (Cupressaceae) has a lifespan of thousands of years. Ancient trees are precious historical heritage and scientific research materials. However, tree aging and tree senescence have different definitions and are poorly understood. Since leaves are the most sensitive organ of a tree, we studied the structural response of leaves to tree age. Experiments investigating the leaf morphological structure, anatomical structure and ultrastructure were conducted in healthy P. orientalis at three different ages (ancient trees >2,000 years, 200 years < middle-aged trees <500 years, young trees <50 years) at the world’s largest planted pure forest in the Mausoleum of the Yellow Emperor, Shaanxi Province, China. Interestingly, tree age did not significantly impact leaf cellular structure. Ancient P. orientalis trees in forests older than 2,000 years still have very strong vitality, and their leaves still maintained a perfect anatomical structure and ultrastructure. Our observations provide new evidence for the unique pattern of tree aging, especially healthy aging. Understanding the relationships between leaf structure and tree age will enhance the understanding of tree aging.

Platycladus orientalis L. (Cupressaceae) has a lifespan of thousands of years. Ancient trees have very high scientific, economic and cultural values. The senescence of ancient trees is a new research area but is poorly understood. Leaves are the primary and the most sensitive organ of a tree. To understand leaf structural response to tree senescence in ancient trees, experiments investigating the morphology, anatomy and ultrastructure were conducted with one-year leaves of ancient P. orientalis (ancient tree >2,000 years) at three different tree senescent levels (healthy, sub-healthy and senescent) at the world’s largest planted pure forest in the Mausoleum of Yellow Emperor, Shaanxi Province, China. Observations showed that leaf structure significantly changed with the senescence of trees. The chloroplast, mitochondria, vacuole and cell wall of mesophyll cells were the most significant markers of cellular ultrastructure during tree senescence. Leaf ultrastructure clearly reflected the senescence degree of ancient trees, confirming the visual evaluation from above-ground parts of trees. Understanding the relationships between leaf structure and tree senescence can support decision makers in planning the protection of ancient trees more promptly and effectively by adopting the timely rejuvenation techniques before the whole tree irreversibly recesses.

Hydroclimatic conditions and related water resources change in the Tibetan Plateau is one of the main concerns for future sustainable development in China. This study presents a 254-year precipitation reconstruction from August of the previous year to June of the current year for the northeastern Tibetan Plateau based on tree-ring width data of tree-ring cores of Picea crassifolia from three sampling sites. The precipitation reconstruction explained 51.4% of the variance in instrumental precipitation during the calibration period 1958–2013. Dry periods with precipitation below the 254-year average value occurred during 1848–1865, 1873–1887, 1898–1923, and 1989–2003, and wet periods (precipitation above the mean) occurred during 1769–1785, 1798–1833, 1924–1938, 1957–1968, and 2004–2013. Spatial correlation analyses with the precipitation gridded dataset showed that our reconstruction contains some strong regional-scale precipitation signals for the upper Yellow River Basin. Our precipitation reconstruction also agreed in general with other dendroclimatic precipitation reconstructions from surrounding regions. In addition, reconstructed precipitation changes were consistent with the streamflow variation of the Yellow River.

Chinese tulip tree (Liriodendron chinensis) is native to China and is planted all around the country as an ornamental tree. In July of 2011, some Chinese tulip trees with typical phytoplasma symptoms were found in Baoding City, Hebei Province, China. Symptoms included yellowing of leaves, slow decline, little leaves, and death of entire plants. To confirm phytoplasma infection of these plants, total DNA was extracted from 100 mg of fresh leaf midribs collected from leaves of nine symptomatic and eight asymptomatic plants with a plant DNA extract kit (Tiangen, Beijing, China) according to the manufacturer's protocols. Using 16S rRNA phytoplasma universal primer pairs P1/P7 followed by R16F2n/R16R2, a nest PCR was carried out (1,2). The results showed that the phytoplasma was only detected in symptomatic samples by nested PCR, while the asymptomatic were negative. An approximate 1.2-kb specific fragment was obtained from the DNA of nine symptomatic plants, but no product was amplified from the leaves of eight healthy ones. The amplified products were cloned and sequenced. The sequence was deposited in GenBank Data Libraries under Accession No. JQ585925 and shared the highest homology of 99% with Puna chicory flat stem phytoplasma (GenBank Accession No. JN582266), Apricot leaf roll phytoplasma (GenBank Accession No. FJ572660), Jujube witches'-broom phytoplasma (GenBank Accession No. AY197661), and other elm yellows group phytoplasmas by BLAST analysis with that of other phytoplasmas from GenBank. Meanwhile, the sequence data was analyzed by iPhyClassifier software and the result showed that the 16S rDNA F2nR2 fragment was identical (similarity coefficient 1.00) to the reference patterns of 16Sr group V, subgroup B (GenBank Accession No.AB052876) (3). Combining the BLAST analysis in GenBank and the analysis of iPhyClassifier, we classified the phytoplasma causing Chinese tulip tree yellow leaves disease into subgroup 16SrV-B. To our knowledge, this is the first report of the 16SrVB group phytoplasmas infecting Chinese tulip tree in China. References: (1) I. M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998. (2) I. M. Lee et al. Int. J. Syst. Evol. Microbiol. 54:337, 2004. (3) Y. Zhao et al. Int. J. Syst. Evol. Microbiol. 59:2582, 2009.

Three new species of Aleurodiscus s.l. with corticioid basidiomata are described and illustrated from southern China based on morphological evidence and phylogenetic analyses of ITS and nrLSU sequence data. Aleurodiscusbambusinus was collected from Jiangxi Province on bamboo and is distinct by having a compact texture, simple-septate generative hyphae, abundant acanthophyses, basidia with acanthophysoid appendages and smooth basidiospores. Aleurodiscusisabellinus was collected from Yunnan Province on both angiosperm wood and bamboo and is distinct by having soft basidiomata with yellow to yellowish-brown hymenophore, yellow acanthophyses, simple-septate generative hyphae and smooth basidiospores. Aleurodiscussubroseus was collected from Guangxi Autonomous Region and Guizhou Province on angiosperm wood and is distinct by having pinkish basidiomata when fresh, clamped generative hyphae, clavate acanthophyses and echinulate basidiospores. In the phylogenetic tree, A.bambusinus and A.isabellinus were nested within the A.cerussatus group, whilst A.subroseus was clustered with A.wakefieldiae. An identification key to 26 species of Aleurodiscus s.l. in China is provided.

Ottelia fengshanensis, a new species (Hydrocharitaceae) from southwest China is here described and illustrated. Comparing its morphological features to putative close relatives O. guanyangensis, it has 3–4 flowers (vs. 2–5) each spathe, hexagonal-cylindric fruit, white styles (vs. yellow), green leaves (vs. dark green) and fruit tiny winged (vs. winged obviously). Molecular phylogenetic investigation of four DNA sequences (ITS, rbcL, trnK5’ intron and trnS-trnG) and the Poisson Tree Processes model for species delimitation (PTP) analysis, further resolves O. fengshanensis as a new species that is close to O. guanyangensis with distinct support.

AbstractThe ecological environment of the headwater area of the Yellow River, west China, is seriously deteriorating because of the harsh natural environment, weakened ecological systems and intensified human activities as well as regional climate changes. Forests and glaciers coexist in this area. Glaciers in the area have retreated over the last decade because of climate change. Most glaciers on the Tibetan Plateau (TP) tend to retreat during warm intervals and advance during cold intervals. Tree-ring records provide an important index for examining past climate changes. A total of 139 core samples from 97 living cypresses (Juniperus przewalskii) in the central region of the Yellow River headwater area, the Animaqin mountains, northeastern TP, were sampled from three sites that are close to each other. The chronologies were developed using the ARSTAN program. Analyses indicate that these tree-ring width records reflect the summer maximum temperature of the study area over the past 700 years. The tree-ring records and the glacier advances recorded by terminal moraines are compared. Inferred summer maximum temperatures suggest three cold periods during the Little Ice Age, around AD1500, 1700 and 1850. These cold intervals are consistent with the glacier moraine record from the region.

Actual evapotranspiration (ETa) is a central process in the climate system and a nexus of the water and energy cycles. This study assesses the hydrological performance of the four categories of ETa products (i.e., land surface models (LSMs), reanalysis, model tree ensemble, and diagnostic models (DMs)) for use in the middle Yellow River Basin (MYRB) using water balance methods. The results show the following. (1) The water storage changes significantly at annual scale and cannot be neglected when calculating the reference ETa by the water balance methods. (2) ETa from LSMs, considering the precipitation input, exhibits the best performance in capturing the reference ETa variation. The MET ETa (AETJUNG), based on eddy covariance, has fair performance with a small underestimation, followed by the DMs, including MODIS and ZhangKe. Poor performance is found in reanalysis ETa (JRA55), due to overestimations precipitation and radiation. (3) The reference ETa showed decreased and then increased trend. ETa from the LSMs-Noah model captures the trend well, followed by the LSMs-variable infiltration capacity model. Our results are not only meaningful for better understanding ETa variability in the MYRB, but also significant for improving global ETa products models' performance in semi-arid and semi-humid regions.

This study uses the mutual information method to study economic dependence among the provinces in the Yellow River Economic Belt, constructs the core dependence structure through the maximum spanning tree method, and uses the rolling window method to observe the changes in the dependence structure from a dynamic point of view. It has been found that there are extensive economic links among the nine provinces in the Yellow River Economic Belt, but that the degree of economic dependence varies greatly in different time periods. When economic development and the capital market are overheated, the interregional dependence is stronger, while the dependence decreases when economic development is in a state of contraction or when the total demand is relatively reduced. In addition, the phenomenon of geographical clustering of economic dependence is not obvious among provinces in the Yellow River Economic Belt. Most of the provinces maintain strong economic dependence with the economically developed provinces, and the economically developed provinces also maintain strong economic ties with one another. Finally, the implementation of the Yellow River Economic Belt strategy strengthens the economic links between the less developed provinces and the other provinces in the region, and promotes coordinated and sustainable development in the region.

Tesis (Grado Doctor en Ciencias Biológicas)--Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Lugar de Trabajo: Instituto de Patología Vegetal-IPAVE- Centro de Investigaciones Agropecuarias-CIAP-Instituto Nacional de Tecnología Agropecuaria-INTA-Universidad Nacional de Córdoba. 2015 - 225 h. con Anexos + CD. ils. col.; grafs.; tabls.; figuras. Contiene Referencia Bibliográfica y Publicaciones Derivadas de la Tesis. Abstract en español e inglés.
En la presente tesis se caracterizaron epidemiológica y molecularmente, fitoplasmas pertenecientes al grupo 16SrXIII, o Mexican periwinkle virescence (MPV) presentes en la Argentina. Se trabajó sobre los patosistemas enrojecimiento letal de la frutilla y amarillamiento del paraíso. Desde el punto de vista epidemiológico, en el patosistema enrojecimiento letal de la frutilla, se determinó que la proporción (incidencia) de plantas con enrojecimiento letal (EL) está estadísticamente relacionados con los cultivares implantados y el origen de los mismos(vivero) .También fue posible relacionar estadísticamente la presencia de la enfermedad EL, con la presencia de fitoplasmas, y se demostró que esta solo puede explicar el 12.08% de los casos. A su vez se logró identificar fitoplasmas de 3 grupos 16Sr distintos (16SrIII, 16SrVII y 16SrXIII) asociados al EL. Dentro de estos grupos, se identificaron fitoplasmas pertenecientes a los subgrupos 16SrIII-J, 16SrIII-X, 16SrVII-C previamente descritos en nuestro país, y el subgrupo 16SrXIII-F, descrito por primera vez en esta tesis. El análisis de las relaciones filogenéticas de estos subgrupos, evidenciaron un parentesco cercano con fitoplasmas de la región Sudamericana, por lo que posiblemente estén siendo dispersados por vectores, de manera local. Por otro lado se detectó por primera vez la presencia del subgrupo 16SrXIII-A en Argentina, el cual solo ha sido reportado en países productores de plantas madres de frutilla (USA), por lo que se presume que el mismo ha ingresado como producto de la comercialización entre ambas regiones. Respecto al patosis tema amarillamiento del paraíso fue posible determinar con precisión la distribución geográfica del fitoplasma China tree yellows ChTYXIII (16SrXIII-C), demostrándose la presencia del mismo solo en la región del nordeste Argentino (Chaco, Formo sa, Misiones y norte de Corrientes). El análisis de los genes 16SrDNA, rpLV-rpsC y secA en distintos aislamientos geográficos del ChTYXIII permitió determinar que dicho patógeno presenta todas las condiciones para ser considerado como una nueva especie de fitoplasma denominada ‗Candidatus Phytoplasma meliae‘ Se generó un antisuero policlonal específico en contra de la proteína secA, el cual permitió localizar al ‗Candidatus Phytoplasma meliae‘ mediante inmunohistoquímica y detectarlo de manera específica. A su vez, se logró poner a punto un sistema de detección específico de dicho patógeno mediante PCR con cebadores generados a partir de secuencias del gen secA. Por último, se caracterizó molecularmente la proteína inmunodominante de membrana del tipo amp del ‗Candidatus Phytoplasma meliae‘. Dicha proteína presenta una región central hidrofílica y dos regiones transmembrana ubicadas en los extremos C-terminal y N-terminal. El análisis de identidad de las distintas regiones, reveló que la región central hidrofílica es altamente diversa, y está sometida a una presión de selección positiva. Estos resultados sugieren la participación de dicha proteína en mecanismos de interacción patógeno-hospedante.

In the house that seems embarrassingly large and mostly empty now that our children are grown and have children of their own, there is a screened-in porch adjacent to the family room on the second floor. When my wife and I sit on this porch during the summer, after the leaves on the old growth trees in our back yard open and many varieties of birds magically appear, it seems, for a moment at least, that all is right with the world. Laurel oaks and Virginia pines tower over a landscape covered in a canopy of intense green leaves, and members of two families of gray squirrels perform acrobatic feats in the maze of limbs and branches. American goldfinch with bright yellow bodies and black wings, northern cardinals with red bodies and orange bills, and pileated woodpeckers with large red crests and moustaches are frequent visitors. After evening comes and the sky begins to grow dark, the magical mystery tour continues as deer and the occasional lone fox or coyote pass through the thick foliage in the woods behind the house. But when we sat on this porch during the summer of 2010, it was not possible to feel even for a moment that all was right with the world. The outside temperature was oppressively hot for most of the day, and there were record-breaking heat waves across the United States, Europe, and Asia. The temperature in South Central Pakistan in May was the highest ever recorded in Asia, 128 degrees Fahrenheit, and the average temperature in Moscow in July was an unprecedented 100 degrees Fahrenheit. In August, scientists at the World Meteorological Organization (WMO) said that research based on enhanced climate models indicated that global warming was responsible for these much higher than average temperatures. The scientists at WMO also concluded that higher temperatures in the Atlantic Ocean and atmospheric anomalies caused by a La Nina created conditions that resulted in the severe draught in Russia, the flooding and mudslides in western China, and the floods that inundated about one-fifth of the landmass in Pakistan.